$50/hr, minimum 3 hours' billing, and ssh-based root access to the box, and I'm sure I could have this licked.

Or, you can just try using CPAN to install DBI (again - force if you have to), then try DBD::DB2.

For chromatic's edification: if vennirajan is right about the package he has installed (with the letters "ADCL"), it's pretty much the only package that you don't get any choice: you always get the DB2 headers. What is missing is the DBI headers.